Factors associated with ankle injuries. Preventive measures

Structural and Organizational Strategies of Locomotor Modules during Landing in Patients with Chronic Ankle Instability

BACKGROUND

Human locomotion involves the coordinated activation of a finite set of modules, known as muscle synergy, which represent the motor control strategy of the central nervous system. However, most prior studies have focused on isolated muscle activation, overlooking the modular organization of motor behavior. Therefore, to enhance comprehension of muscle coordination dynamics during multi-joint movements in chronic ankle instability (CAI), exploring muscle synergies during landing in CAI patients is imperative.

METHODS

A total of 22 patients with unilateral CAI and 22 healthy participants were recruited for this research. We employed a recursive model for second-order differential equations to process electromyographic (EMG) data after filtering preprocessing, generating the muscle activation matrix, which was subsequently inputted into the non-negative matrix factorization model for extraction of the muscle synergy. Muscle synergies were classified utilizing the K-means clustering algorithm and Pearson correlation coefficients. Statistical parameter mapping (SPM) was employed for temporal modular parameter analyses.

RESULTS

Four muscle synergies were identified in both the CAI and healthy groups. In Synergy 1, only the gluteus maximus showed significantly higher relative weight in CAI compared to healthy controls (p = 0.0035). Synergy 2 showed significantly higher relative weights for the vastus lateralis in the healthy group compared to CAI (p = 0.018), while in Synergy 4, CAI demonstrated significantly higher relative weights of the vastus lateralis compared to healthy controls (p = 0.030). Furthermore, in Synergy 2, the CAI group exhibited higher weights of the tibialis anterior compared to the healthy group (p = 0.042).

CONCLUSIONS

The study suggested that patients with CAI exhibit a comparable modular organizational framework to the healthy group. Investigation of amplitude adjustments within the synergy spatial module shed light on the adaptive strategies employed by the tibialis anterior and gluteus maximus muscles to optimize control strategies during landing in patients with CAI. Variances in the muscle-specific weights of the vastus lateralis across movement modules reveal novel biomechanical adaptations in CAI, offering valuable insights for refining rehabilitation protocols.

The Effectiveness of Proprioceptive Training for Improving Motor Performance and Motor Dysfunction: A Systematic Review

Objective

Proprioceptive training is any intervention aiming to improve proprioceptive function with the ultimate goal to enhance motor function and performance. It has been promoted as an approach to enhance athletic performance and as a tool for sensorimotor rehabilitation. Numerous studies sought to provide evidence on the effectiveness of the approach. However, many different training regimes claiming to train proprioception report a variety of sensorimotor measures that are not directly comparable. This, in turn, makes it difficult to assess effectiveness across approaches. It is the objective of this study to systematically review recent empirical evidence to gain an understanding of which outcome measures are most sensitive, which populations may benefit most from proprioceptive training, and what are the effects on proprioceptive and motor systems.

Methods

Four major databases were searched. The following inclusion criteria were applied: (1) A quantified pre- and post-treatment measure of proprioceptive function. (2) An intervention or training program believed to influence or enhance proprioceptive function. (3) Contained at least one form of treatment or outcome measure that is indicative of somatosensory function and not confounded by information from other sensory modalities. 4) The study reported of at least one quantified measure of motor performance.

Results

Of the 3,297 articles identified by the database search, 70 studies met the inclusion criteria and were included for further review. Across studies, proprioceptive training led to comparable gains in both proprioceptive (+46%) and motor performance (+45%). The majority of studies (50/70) applied active movement interventions. Interventions applying somatosensory stimulation were most successful in clinical populations. Joint position sense error (JPSE) was the most commonly used proprioceptive measure and presents a reliable and feasible measure for clinical use.

Conclusion

Proprioceptive training can lead to significant improvements in proprioceptive and motor function across a range healthy and clinical populations. Regimens requiring active movement of the trainee tended to be most successful in improving sensorimotor performance. Conclusive evidence on how long training gains are retained is still lacking. There is no solid evidence about the underlying long-term neuroplastic changes associated proprioceptive training.

Hip Abductor Muscle Strength Deficit as a Risk Factor for Inversion Ankle Sprain in Male College Soccer Players: A Prospective Cohort Study

Background:

Previous studies have attempted to determine whether certain risk factors can predict the occurrence of inversion ankle sprains in male collegiate soccer players. However, no consensus has been reached on the predictive risk factors of inversion ankle sprain in this population.

Purpose:

To identify risk factors for inversion ankle sprains among male collegiate soccer players.

Study Design:

Cohort study; Level of evidence, 2.

Methods:

Included were 145 male collegiate soccer players in Japan who were assessed during a preseason medical checkup for potential risk factors of inversion ankle sprain. The preseason assessment included anthropometric measurements, joint laxity and flexibility, muscle flexibility, muscle strength, and balance ability, with a total of 33 variables. The participants were monitored during the 2019 season for inversion ankle sprains as diagnosed by physicians.

Results:

A total of 31 inversion ankle sprains in 31 players (21.4%) occurred during the season. Only the measured isometric hip abductor strength was significantly lower in injured players as compared with uninjured players. Logistic regression analysis revealed measured hip abductor muscle strength deficit as a significant risk factor for inversion ankle sprain (odds ratio, 0.978 [95% CI, 0.976-0.999]; P = .05).

Conclusion:

Hip abductor strength deficit was a risk factor for inversion ankle sprain in the study population. This finding could be useful for the prevention of inversion ankle sprains in male collegiate soccer players.

Selective effect of static stretching, concentric contractions, and a balance task on ankle force sense

Proper ankle motor control is critical for balance in the human body during functional activities such as standing, walking, and running. Different exercise modalities are often performed during the same training session where earlier activities may influence later ones. The purpose of the current study was to determine the acute effects of different exercise modalities on ankle force sense. Seventeen subjects performed four different intervention protocols (static stretching, balance task, concentric contractions, and control) in random order. Each session comprised measurements before and after the intervention protocol of the force sense of the ankle plantar flexors (PF) and dorsal flexors (DF) at 10% and 30% of maximal voluntary isometric contraction (MVC). Absolute errors (AE) were calculated separately for each force level and muscle group. An overall PF error (PF-SUM = PF at 10%MVC + PF at 30%MVC), DF error (DF-SUM = DF at 10%MVC + DF at 30%MVC) and ankle error (PF-DF-SUM = PF-SUM + DF-SUM) were also calculated. The main effect of time generally revealed that ankle force sense was significantly reduced after static stretching (PF-DF-SUM: Pre: 6.11±2.17 Nm, Post: 8.03±3.28 Nm; p < 0.05), but no significant differences were observed for the concentric contractions (PF-DF-SUM: Pre: 6.01±1.97 Nm, Post: 6.50±2.28 Nm) and the balance task (PF-DF-SUM: Pre: 5.25±1.97 Nm, Post: 5.50±1.26 Nm). The only significant interaction was observed for the PF-DF-SUM (F = 4.48, p = 0.008) due to greater error scores after stretching (+31.4%) compared to the concentric (+8.2%), balance (+4.8%), and control (-3.5%) conditions. Based on these results, static stretching should not be performed before activities that require a high ankle force sense such as balance, coordination, and precision tasks.

The effect of anxiety on anticipation, allocation of attentional resources, and visual search behaviours

Successful sports performance requires athletes to be able to mediate any detrimental effects of anxiety whilst being able to complete tasks simultaneously. In this study, we examine how skill level influences the ability to mediate the effects of anxiety on anticipation performance and the capacity to allocate attentional resources to concurrent tasks. We use a counterbalanced, repeated measures design that required expert and novice badminton players to complete a film-based anticipation test in which they predicted serve direction under high- and low-anxiety conditions. On selected trials, participants completed an auditory secondary task. Visual search data were recorded and the Mental Readiness Form v-3 was used to measure cognitive anxiety, somatic anxiety and self-confidence. The Rating Scale of Mental Effort was used to measure mental effort. The expert players outperformed their novice counterparts on the anticipation task across both anxiety conditions, with both groups anticipation performance deteriorating under high- compared to low-anxiety. This decrease across anxiety conditions was significantly greater in the novice compared to the expert group. High-anxiety resulted in a shorter final visual fixation duration for both groups when compared to low-anxiety. Anxiety had a negative impact on secondary task performance for the novice, but not the expert group. Our findings suggest that expert athletes more effectively allocated attentional resources during performance under high-anxiety conditions. In contrast, novice athletes used more attentional resources when completing the primary task and, therefore, were unable to maintain secondary task performance under high-anxiety.

Barefoot Running Reduces the Submaximal Oxygen Cost in Female Distance Runners

Berrones, AJ, Kurti, SP, Kilsdonk, KM, Cortez, DJ, Melo, FF, and Whitehurst, M. Barefoot running reduces the submaximal oxygen cost in female distance runners. J Strength Cond Res 30(8): 2348-2353, 2016-Being a competitive distance runner is, in part, attributable to a high V[Combining Dot Above]O2max. However, running economy (RE) is a more robust indicator of distance running performance among endurance athletes of similar V[Combining Dot Above]O2max levels. The purpose of this study was to examine the influence of unshod (barefoot) vs. shod (wearing shoes) running on RE (expressed as ml·kg·min) during three 5-minute submaximal running trials representing 65, 75, and 85% of V[Combining Dot Above]O2max. Other physiologic and perceptual variables such as respiratory exchange ratio, lactate, heart rate, and ratings of perceived exertion were also chosen as dependent variables. We measured V[Combining Dot Above]O2max in 14 recreationally active trained distance female runners (age = 27.6 ± 1.6 years; height = 163.3 ± 1.7 cm; weight = 57.8 ± 1.9 kg) who were completely inexperienced with unshod running. After initial testing, each subject was randomized to either unshod or shod for days 2 and 3. We analyzed the data with a 2-way (condition by intensity) repeated-measures analysis of variance. Submaximal oxygen consumption was significantly reduced at 85% of V[Combining Dot Above]O2max (p = 0.018), indicating an improvement in RE, but not during the 65% or 75% trials (p > 0.05, both). No other dependent measure was different between unshod and shod conditions. Our results indicate that the immediate improvement to RE while barefoot occurs at a relatively high fraction of maximal oxygen consumption. For the recreational or competitive distance runner, training or competing while barefoot may be a useful strategy to improve endurance performance.

FACTORS LEADING TO LATERAL ANKLE SPRAIN: A REVIEW OF THE LITERATURE

Objective of the review is to get to know the different factors which leads to the most common injury associated with sports persons to the ankle that is the lateral ankle sprain. Many factors cause ankle sprain — gender (whether females are more predisposed to ankle sprain than males); anthropometric variability and limb dominance, muscle strength including evertors–invertor's strength and pro-activation of peroneal muscles. Previous episode of ankle sprain also affects the stability as it alters the proprioception leading to impaired neuromuscular facilitation. Joint laxity (pathological — due to injury and nonpathological — generalized body laxity) is also considered as another causative factor. Type and duration of the game or putting the assistive device during the game or training also contribute to the ankle sprain. By knowing the predisposing factors, athletes will be given more specific rehabilitation according to their risk factor, especially focusing on their advance rehabilitation. Athletes can also be taught to take the preventive measures by determining their risk factor and preparing according to it.

EVALUATION OF PERIPHERAL AND FOCAL VISION in PROPRIOCEPTIVE DIFFERENTIATION OF UNDERFOOT INVERSION ANGLES: COMMENT ON WITCHALLS, ET AL. (2013) (.)

A study by Witchalls, et al. (2013) mentioned that the addition of focal vision to proprioception testing with walking produces greater proprioceptive acuity than peripheral vision alone (measured ankle proprioception in athletes with or without chronic ankle instability during a stepping task on the Active Movement Extent Discrimination Apparatus; AMEDA). According to this study, people with impaired proprioception, e.g., athletes with chronic ankle instability, may profit from looking down during walking or running. This commentary notes that the active stepping task may not be truly comparable to rhythmic stepping, which is characteristic for walking. In addition, we suggest several amendments to the methodology for further studies related to ankle proprioception measurement, e.g., monitoring of proband eye attention during a stepping task or clear objective evaluation of the subject sample.

A Survey of Runners' Attitudes Toward and Experiences With Minimally Shod Running

OBJECTIVE

To investigate the characteristics, perceptions, motivating factors, experiences, and injury rates of runners who practice minimally shod running.

DESIGN

Survey.

SETTING

web-based questionnaire.

PARTICIPANTS

Five-hundred sixty-six members of the Chicago Area Runner's Association.

METHODS

A link to a 31-question online survey was e-mailed to members of Chicago Area Runner's Association. Questions covered demographic information, use of minimalist-style running shoes (MSRS), injury rates, and change in pain.

MAIN OUTCOME MEASURES

Use of MSRS, occurrence or improvement of injury/pain, regions of injury/pain, reasons for or for not using MSRS.

RESULTS

One-hundred seventy-five (31%) respondents had practiced minimally shod running, and the most common motivating factor was to decrease injuries and/or pain. Fifty-one respondents (29%) suffered an injury or pain while wearing MSRS, with the most common body part involved being the foot. Fifty-four respondents (31%) had an injury that improved after adopting minimally shod running; the most common area involved was the knee. One-hundred twenty respondents (69%) were still using MSRS. Of those who stopped using MSRS, the main reason was development of an injury or pain. The most common reason that respondents have not tried minimally shod running is a fear of developing an injury.

CONCLUSION

This survey-based study demonstrated that the use of MSRS is common, largely as the result of a perception that they may reduce injuries or pain. Reductions and occurrences of injury/pain with minimally shod running were reported in approximately equal numbers. The most common site of reported injury/pain reduction was the knee, whereas the most common reported site of injury/pain occurrence was the foot. Fear of developing pain or injury is the most common reason runners are reluctant to try minimally shod running.

The risks and benefits of running barefoot or in minimalist shoes: a systematic review

Context:

The popularity of running barefoot or in minimalist shoes has recently increased because of claims of injury prevention, enhanced running efficiency, and improved performance compared with running in shoes. Potential risks and benefits of running barefoot or in minimalist shoes have yet to be clearly defined.

Objective:

To determine the methodological quality and level of evidence pertaining to the risks and benefits of running barefoot or in minimalist shoes.

Data Sources:

In September 2013, a comprehensive search of the Ovid MEDLINE, SPORTDiscus, and CINAHL databases was performed by 2 independent reviewers.

Study Selection:

Included articles were obtained from peer-reviewed journals in the English language with no limit for year of publication. Final inclusion criteria required at least 1 of the following outcome variables: pain, injury rate, running economy, joint forces, running velocity, electromyography, muscle performance, or edema.

Study Design:

Systematic review.

Level of Evidence:

Level 3.

Data Extraction:

Two reviewers appraised each article using the Downs and Black checklist and appraised each for level of evidence.

Results:

Twenty-three articles met the criteria for this review. Of 27 possible points on the Downs and Black checklist, articles scored between 13 and 19 points, indicating a range of evidence from very limited to moderate. Moderate evidence supports the following biomechanical differences when running barefoot versus in shoes: overall less maximum vertical ground reaction forces, less extension moment and power absorption at the knee, less foot and ankle dorsiflexion at ground contact, less ground contact time, shorter stride length, increased stride frequency, and increased knee flexion at ground contact.

Conclusion:

Because of lack of high-quality evidence, no definitive conclusions can be drawn regarding specific risks or benefits to running barefoot, shod, or in minimalist shoes.

Effectiveness of a heel cup with an arch support insole on the standing balance of the elderly

Background

The use of insoles may enhance postural stability and prevent falls. The aim of this study was to design a new insole and to explore the effectiveness of the insole on the standing balance of the healthy elderly.

Methods

The study was conducted at a community hospital. Patients older than 65 years at an outpatient clinic without abnormal gait patterns, lower limb deformities, or foot pain were enrolled. The participants were assigned to good- and poor-stability groups on the basis of the stability index (SI), using the Biodex® Balance System. A heel cup with an arch support insole was provided. Participants wore the insole for 8 weeks for a minimum of 4 hours/day. A static balance test for SI was performed at the initial meeting and 8 weeks after the assigned insoles were worn for each participant.

Results

Five participants (10.0%) of 50 total did not finish the study. There were 25 patients in the good-stability group and 20 in the poor-stability group. The SI, before and after intervention, was significantly different for all 45 participants (3.244±0.688 versus 3.064±0.671; P<0.001). The differences in SI before and after the intervention both in the good-stability group (2.764±0.546 versus 2.592±0.538) and the poor-stability group (3.845±0.188 versus 3.655±0.128) were statistically significant (P<0.001). No statistically significant difference on changes of SI were seen between the two groups.

Conclusion

The results suggest a heel cup with arch support insole is effective in enhancing the standing balance of the elderly. This may be of benefit in preventing falls.

A theoretical perspective on running-related injuries

The etiology of running-related injuries remains unknown; however, an implicit theory underlies much of the conventional research and practice in the prevention of these injuries. This theory posits that the cause of running-related injuries lies in the high-impact forces experienced when the foot contacts the ground and the subsequent abnormal movement of the subtalar joint. The application of this theory is seen in the design of the modern running shoe, with cushioning, support, and motion control. However, a new theory is emerging that suggests that it is the use of these modern running shoes that has caused a maladaptive running style, which contributes to a high incidence of injury among runners. The suggested application of this theory is to cease use of the modern running shoe and transition to barefoot or minimalist running. This new running paradigm, which is at present inadequately defined, is proposed to avoid the adverse biomechanical effects of the modern running shoe. Future research should rigorously define and then test both theories regarding their ability to discover the etiology of running-related injury. Once discovered, the putative cause of running-related injury will then provide an evidence-based rationale for clinical prevention and treatment.

Residual mechanical effectiveness of external ankle tape before and after competitive professional soccer performance

OBJECTIVE

To evaluate the presupposed preventive residual mechanical effectiveness of the widespread use of adhesive elastic ankle tape after a nonlaboratory, realistic soccer-specific outfield intervention reflecting a soccer halftime.

DESIGN

A prospective nonrandomized test-retest design was used.

SETTING

Laboratory.

PARTICIPANTS

Seventeen professional male outfield players (mean age, 25.5) without any signs of chronic ankle instability.

INTERVENTION

Participants were investigated before and after a 45-minute soccer-specific field intervention.

MAIN OUTCOME MEASURES

The passive inversion range of motion (ROM) of the ankle was tested unloaded on a self-developed inversion device with and without a standardized ankle tape before and after the intervention. Additionally, electromyography signal was taken to assure the inactivity of the protective evertor muscles, and reliability tests for the inversion device (test-retest and trial to trial) were conducted in 12 healthy controls.

RESULTS

Tape restricted the maximum passive inversion ROM of the uninjured ankle significantly to 50.3%. The protection declined nearly completely after 45 minutes of outfield soccer performance to a negligible nonsignificant ROM restriction of 9.7%. Pearson correlation coefficient for the reliability was 0.931 (P ≤ 0.001) for the test-retest and 0.983 (P ≤ 0.001) for the trial-to-trial test.

CONCLUSIONS

The initial significant protection of external ankle-tape support declines almost completely without relevant remaining residual mechanical effect after 45 minutes, reflecting a soccer halftime. The so far presupposed residual mechanical effectiveness of tape to prevent injury is increasingly irrelevant during soccer performance and consequently antidromic to the increasing injury risk toward the end of a soccer halftime.

Ankle kinematics and muscle activity in functional ankle instability

OBJECTIVE

Following an ankle injury, many patients have functional ankle instability (FAI) with an increased predisposition to reinjury. The purpose of this study was to assess the effects of FAI on ankle kinematics and muscle activity during a lateral hop movement.

DESIGN

Cross-sectional and observational study; all data collection for each subject was performed on 1 day.

SETTING

Clinical biomechanics laboratory.

PATIENTS

Two groups were studied: (1) Control group-no ankle injury (n = 12), and (2) FAI group (n = 12).

INTERVENTIONS

The lateral hop movement consisted of multiple lateral and medial 1-legged hops over an obstacle (width, 72.5 cm; depth, 25.5 cm; height, 14.3 cm) onto adjacent force platforms. Each subject was instructed to perform as many lateral hops as possible during the 6-second trial. Means, SDs, 95% confidence intervals of the differences, and P-values were calculated.

MAIN OUTCOME MEASURES

Ankle kinematics and muscle activity throughout the lateral hop movement.

RESULTS

Significant differences existed between groups for mean (SD) dorsiflexion ankle positions--FAI 82.4 degrees (6.4) versus normal 75.2 degrees (10.1) and tibialis anterior normalized muscle activity--FAI 0.27 (0.21) versus normal 0.16 (0.13) at ground contact.

CONCLUSIONS

The FAI group revealed greater tibialis anterior muscle activity and dorsiflexion ankle position at contact moving in the lateral direction. These differences between groups may have been related to an inherent predisposition to ankle injuries, a preexisting difference in task performance, a consequence of injuries, or a compensatory adaptation to previous injuries.

Aquatic training for ankle instability

The aim of the present study was to evaluate balance deficits after an ankle sprain in collegiate students and to examine the effectiveness of 2 different balance rehabilitation programs on balance ability. Thirty collegiate students with functional ankle instability were randomly divided into 2 groups. Both groups followed an intervention balance program for 6 weeks, 3 times per week, 20 minutes per session, using balance boards. One of the 2 training groups performed the exercises on the ground-the "Land" group (n = 15), and the other in a swimming pool-the "Aquatic" group (n = 15). Balance ability was assessed before and after the 6-week intervention program. Balance assessments included static (stability indices: total, anterior-posterior, medial-lateral) and dynamic (dynamic moving the cursor) stability tests on the Biodex Stability System (Biodex, Inc, Shirley, NY). The results showed that in both training groups balance ability of the injured leg was significantly improved after the training period. In the final measurements, no statistically significant differences between the injured and healthy limb were found. The present study indicates that the performance of balance exercises in or out of water by collegiate students with functional ankle instability improves their balance ability.

LEVEL OF EVIDENCE

Therapeutic, Level 1.

A comparison of electromyography of gluteus medius and maximus in subjects with and without chronic ankle instability during two functional exercises

OBJECTIVE

To determine how gluteus medius (Gmed) and maximus (Gmax) activate during closed-chain functional rehabilitative exercises in those with and without chronic ankle instability (CAI).

DESIGN

Cohort study. Subjects performed ten repetitions of a rotational lunge and single-leg rotational squat while surface electromyography was used to collect mean muscle activity of the Gmed and Gmax.

MAIN OUTCOME MEASURES

Mean electromyography activity of the Gmed and Gmax at maximum excursion was compared between Groups and Exercises using a separate 2-way repeated measures analysis of variance design for each muscle.

SETTING

University biomechanics lab.

PARTICIPANTS

Nine healthy (8F, 1M) and nine CAI subjects (8F, 1M) RESULTS: For Gmax activation, there was a statistically significant Group by Exercise interaction (F(3,48) = 4.84, p = 0.043). A Scheffe's post-hoc test revealed that during the rotational squat, the CAI group had significantly lower Gmax activation (51.1 ± 31.0%) than the healthy group (78.6 ± 44.8%). There were no statistically significant findings for the Gmed. In the healthy group, the Gmax produced significantly higher activation during rotational squat (78.6 ± 44.8%) compared to the rotational lunge (57.6 ± 31.9%).

CONCLUSION

Because the CAI group had significantly less Gmax activation than the healthy group during the rotational squat at the point of maximum excursion, and because the rotational squat showed significantly higher Gmax activation compared to the rotational lunge, it may be important for clinicians to implement the rotational squat during rehabilitation for those with CAI. Future prospective and intervention research involving hip musculature in those with CAI is recommended.

Barefoot running claims and controversies: a review of the literature

BACKGROUND

Barefoot running is slowly gaining a dedicated following. Proponents of barefoot running claim many benefits, such as improved performance and reduced injuries, whereas detractors warn of the imminent risks involved.

METHODS

Multiple publications were reviewed using key words.

RESULTS

A review of the literature uncovered many studies that have looked at the barefoot condition and found notable differences in gait and other parameters. These findings, along with much anecdotal information, can lead one to extrapolate that barefoot runners should have fewer injuries, better performance, or both. Several athletic shoe companies have designed running shoes that attempt to mimic the barefoot condition and, thus, garner the purported benefits of barefoot running.

CONCLUSIONS

Although there is no evidence that either confirms or refutes improved performance and reduced injuries in barefoot runners, many of the claimed disadvantages to barefoot running are not supported by the literature. Nonetheless, it seems that barefoot running may be an acceptable training method for athletes and coaches who understand and can minimize the risks.

The Epidemiology of Ankle Sprain during Hiking in Uniformed Groups

Purpose

To determine the prevalence of ankle sprain during hiking training in uniformed groups and identify the risk factors of ankle sprain and the risk factors associated with residual problems after ankle sprain.

Methods

A retrospective cross-sectional study involved 590 members of a uniformed group from secondary schools and their leaders by means of a self-administered anonymous questionnaire.

Results

The prevalence of ankle sprain was 9.15%. Most of them were lateral sprains (70.4%) and occurred in scree ground (51.9%) and downhill slope (50.0%). Subjects who are “older” aged, are overweight, are leaders in uniformed groups, have a past history of ankle sprain or problem, have a long-term lower limb injury, wear inadequate sized or tight shoes, and use hiking poles, have significant risks. The prevalence of having residual problems after ankle sprains was 48.14%, and the most common one was residual ankle pain (25.0%).

Conclusion

Uniformed group leaders and members should be aware of the risk factors of ankle sprain during hiking training in the countryside. They should also be aware of the importance of proper treatment and rehabilitation to prevent residual ankle problem.

Level of Evidence

Level II prognostic study.

Ankle sprains: patient perceptions of function and performance of physical tasks. A mixed methods approach

PURPOSE

To investigate patient's perceptions of function and performance of physical tasks after discharge from treatment for an ankle sprain.

METHODS

Using a mixed methods approach, 40 participants who presented with an acute sprained ankle and their treating clinicians completed two questionnaires related to function at the start and end of a rehabilitation programme. Additionally, participants completed the questionnaires at 6 weeks following discharge at which time they also performed physical tasks that were still perceived as difficult. Ten participants also completed a semi-structured interview.

RESULTS

There were no significant differences (p > 0.05) in the participant's and clinician's initial assessment of function. However, at discharge participants scored their function significantly (p < 0.05) lower than clinicians. This difference was not apparent 6 weeks later (p > 0.05). However, there was a significant difference (p  < 0.05) following actual performance of tasks with an effect size of 1.58. Participant interviews confirmed that patients had a fear of re-injury until they actually performed tasks that were perceived as difficult.

CONCLUSIONS

Clinicians and participants do not have a similar perception of the recovery of an ankle sprain at discharge. Performing tasks which were perceived as difficult were valuable in assisting participants gain an improved appreciation of their function.

The influence of a balance training program on the electromyographic latency of the ankle musculature in subjects with no history of ankle injury

BACKGROUND

Balance training is often employed for the prevention of ankle injuries. However, until now, most of the studies have focused on the prevention of a recurrent injury. The objective of this study was to look into the effects of balance training on the onset of peroneal muscle activity in healthy subjects.

METHODS

34 participants (mean age = 19.5 years ± 1.5; height = 1.70 m ± 0.12; weight = 62.06 kg ± 11.24), physically active, with no history of injuries took part in this study. The participants underwent a 4-week balance training program using an ankle disk. Onset of peroneal muscles activation was measured using surface electromyography and a trap-door.

FINDINGS

Parametric and non-parametric tests showed no significant differences between the control group and the experimental group (P > 0.05).

INTERPRETATION

The results indicate that the use of balance training, for a 4-week period with two training sessions per week, on physically active subjects with no history of injuries in the ankle joint, does not cause noteworthy changes on the onset of peroneal muscles activity.

Twelve-week biomechanical ankle platform system training on postural stability and ankle proprioception in subjects with unilateral functional ankle instability

BACKGROUND

Functional ankle instability is defined as the subjective sensation of giving way or feeling joint instability after repeated episodes of ankle sprain. The purpose of this study was to examine the effects of 12-week biomechanical ankle platform system training on static postural stability and ankle reposition sense in subjects with unilateral functional ankle instability.

METHODS

Twelve university students (4 females and 8 males) with unilateral functional ankle instability volunteered as subjects. The active and passive reposition senses were assessed using an isokinetic dynamometer. The mean radius of the center of pressure excursion was recorded during single-leg standing with a force platform. A 12-week training program and a progression test for controlling the platform in certain directions and advancing to next training level was given to each subject. Repeated-measures 2-way analyses of variance were conducted to determine differences in postural stability and ankle proprioception between each limb before and after the training period.

FINDINGS

The mean radius of center of pressure on unilateral standing and the absolute error from pre-selected ankle angle in the functional ankle instability limb were significantly reduced after 12 weeks of training.

INTERPRETATION

These improvements in postural stability appear to reflect improved neuromuscular ability along with enhanced functional joint stability, as ankle proprioception also demonstrated the same positive improvements after training.

The role of shoe design in ankle sprain rates among collegiate basketball players

CONTEXT

Much of the recent focus in shoe design and engineering has been on improving athletic performance. Currently, this improvement has been in the form of "cushioned column systems," which are spring-like in design and located under the heel of the shoe in place of a conventional heel counter. Concerns have been raised about whether this design alteration has increased the incidence of ankle sprains.

OBJECTIVE

To examine the incidence of lateral ankle sprains in collegiate basketball players with regard to shoe design.

DESIGN

Prospective cohort study.

SETTING

Certified athletic trainers at 1014 National Collegiate Athletic Association (NCAA)-affiliated schools sponsoring basketball during the 2005-2006 regular season were notified of an online questionnaire. Athletic trainers at 22 of the 1014 schools participated.

PATIENTS OR OTHER PARTICIPANTS

A total of 230 basketball players (141 males, 89 females; age = 20.2 +/- 1.5 years) from NCAA Division I-III basketball programs sustained lateral ankle sprains.

MAIN OUTCOME MEASURE(S)

Ankle sprain information and type of shoe worn (cushioned column or noncushioned column) were collected via online survey. The incidence of lateral ankle sprains and type of shoes worn were compared using a chi-square analysis.

RESULTS

No difference was noted in ankle sprain incidence between groups (chi(2) = 2.44, P = .20, relative risk = 1.47, 95% confidence interval [CI] = 0.32, 6.86). The incidence of ankle sprains was 1.33 per 1000 exposures in the cushioned column group (95% CI = 0.62, 3.51) and 1.96 per 1000 exposures in the noncushioned column group (95% CI = 0.51, 4.22).

CONCLUSIONS

No increased incidence of ankle sprains was associated with shoe design.

Ankle bracing, fatigue, and time to stabilization in collegiate volleyball athletes

CONTEXT

Fatigue has been shown to disrupt dynamic stability in healthy volunteers. It is not known if wearing prophylactic ankle supports can improve dynamic stability in fatigued athletes.

OBJECTIVE

To determine the type of ankle brace that may be more effective at providing dynamic stability after a jump-landing task during normal and fatigued conditions.

DESIGN

Two separate repeated-measures analyses of variance with 2 within-subjects factors (condition and time) were performed for each dependent variable.

SETTING

Research laboratory.

PATIENTS OR OTHER PARTICIPANTS

Ten healthy female collegiate volleyball athletes participated (age = 19.5 +/- 1.27 years, height = 179.07 +/- 7.6 cm, mass = 69.86 +/- 5.42 kg).

INTERVENTION(S)

Athletes participated in 3 separate testing sessions, applying a different bracing condition at each session: no brace (NB), Swede-O Universal lace-up ankle brace (AB), and Active Ankle brace (AA). Three trials of a jump-landing task were performed under each condition before and after induced functional fatigue. The jump-landing task consisted of a single-leg landing onto a force plate from a height equivalent to 50% of each participant's maximal jump height and from a starting position 70 cm from the center of the force plate.

MAIN OUTCOME MEASURE(S)

Time to stabilization in the anterior-posterior (APTTS) and medial-lateral (MLTTS) directions.

RESULTS

For APTTS, a condition-by-time interaction existed (F(2,18) = 5.55, P = .013). For the AA condition, Tukey post hoc testing revealed faster pretest (2.734 +/- 0.331 seconds) APTTS than posttest (3.817 +/- 0.263 seconds). Post hoc testing also revealed that the AB condition provided faster APTTS (2.492 +/- 0.271 seconds) than AA (3.817 +/- 0.263 seconds) and NB (3.341 +/- 0.339 seconds) conditions during posttesting. No statistically significant findings were associated with MLTTS.

CONCLUSIONS

Fatigue increased APTTS for the AA condition. Because the AB condition was more effective than the other 2 conditions during the posttesting, the AB appears to be the best option for providing dynamic stability in the anterior-posterior direction during a landing task.

Estudo epidemiológico da entorse de tornozelo em atletas de voleibol de alto rendimento

O objetivo desta pesquisa foi caracterizar o último episódio de entorse de tornozelo em atletas de voleibol de alto rendimento. Participaram inicialmente deste estudo, entre os meses janeiro de 2003 e março de 2004, 114 atletas, do sexo masculino, atuantes na categoria adulta de 9 equipes, todas participantes da Divisão Especial ou Primeira Divisão do Campeonato Paulista de Voleibol. Dos 114 atletas inicialmente analisados, 21 relataram não ter sofrido nenhuma lesão nos tornozelos, portanto, seguindo os critérios de exclusão, foram analisados 93 episódios de última entorse de tornozelo de 93 atletas. Os mesmos foram entrevistados de maneira oral e individual pelo pesquisador executante, seguindo a seqüência do questionário pré-estabelecido. Foi encontrada diferença significante na correlação entre a fase da competição e a causa da entorse bem como na relação entre a posição de atuação do atleta e o fundamento realizado no momento da lesão. A posição oposto foi a mais acometida e o fundamento bloqueio foi o que mais ocasionou entorses.

Injury prevention during physical activity in the Australian Defence Force

INTRODUCTION

Injuries sustained by Australian Defence Force (ADF) personnel during non-combat military training and sports activity are associated with increasing costs due to work days lost, medical treatment, compensation, and early retirement. In 2001, the ADF commissioned a systematic review of the evidence-base for reducing injuries associated with physical activity, while at the same time improving physical activity participation rates to sustain a trained, fit and deployable workforce.

METHOD

Literature from on-line library databases, relevant unclassified military reports, and material from previously published sport-specific injury countermeasure reviews were systematically and critically analysed to address the study aims.

RESULTS

Modification of intensity, frequency and duration of basic military training activities and improved equipment is likely to reduce injury occurrence. Sports injury countermeasures used for the civilian population have merit for the ADF physical activity program. Injury countermeasures should be designed to minimise any possible deterrent effect on the motivation to participate in regular physical activity. Increasing the participation of ADF personnel in physical activity in the presence of evidence-based injury prevention strategies has the potential to increase health, fitness and deployability with minimal impact on injury frequency.

CONCLUSION

Recommendations arising from the review include injury intervention trials in basic military training and sports. These and other interventions should be supported by refinement to ADF injury surveillance systems. Research should focus on interventions with the greatest gain for fitness, deployability, and cost effectiveness.

Comparison of three preventive methods in order to reduce the incidence of ankle inversion sprains among female volleyball players

BACKGROUND

Ankle sprains are the most common form of acute injury in volleyball. A prevention programme consisting of technical training, proprioceptive training, and external support was previously designed to reduce the rate of ankle sprains in volleyball players.

OBJECTIVE

To investigate which of these three interventions is the most effective in preventing ankle sprain in female volleyball players.

METHODS

Participants were 52 players who suffered ankle sprains during the season 1998-1999. They were divided randomly into three preventive groups: group 1 (n = 18) followed the technical training programme; group 2 (n = 17) followed the proprioceptive programme; group 3 (n = 17) used orthosis. The players followed their respective programmes for the whole of the 1999-2000 season. Data were collected at the end of the season.

RESULTS

The three preventive strategies were all effective in preventive further ankle sprain. Technical training was slightly more effective than the other two methods. Orthosis was not effective in athletes who had suffered ankle sprains more than three times during their careers. Under those circumstances, technical training and proprioceptive training were equally effective at preventive further sprains.

CONCLUSIONS

Technical training and proprioceptive training are effective methods of preventing ankle sprain in volleyball players who have suffered this injury four or more times during their career. Orthosis appears effective only in players with fewer than four previous sprains.

The Football Association Medical Research Programme: an audit of injuries in professional football: an analysis of ankle sprains

AIM

To conduct a detailed analysis of ankle sprains sustained in English professional football over two competitive seasons.

METHODS

Club medical staff at 91 professional football clubs annotated player injuries. A specific injury audit questionnaire was used together with a weekly form that documented each club's current injury status.

RESULTS

Completed injury records for the two competitive seasons were obtained from 87% and 76% of the participating clubs. Ankle ligament sprains accounted for 11% of the total injuries over the two seasons, with over three quarters (77%) of sprains involving the lateral ligament complex. A total of 12 138 days and 2033 matches were missed because of ankle sprains. More sprains were caused by contact mechanisms than non-contact mechanisms (59% v 39%) except in goalkeepers who sustained more non-contact sprains (21% v 79%, p<0.01). Ankle sprains were most often observed during tackles (54%). More ankle sprains were sustained in matches than in training (66% v 33%), with nearly half (48%) observed during the last third of each half of matches. A total of 44% of sprains occurred during the first three months of the season. A high number of players (32%) who sustained ankle sprains were wearing some form of external support. The recurrence rate for ankle sprains was 9% (see methodology for definition of reinjury).

CONCLUSION

Ankle ligament sprains are common in football usually involving the lateral ligament complex. The high rate of occurrence and recurrence indicates that prevention is of paramount importance.

Effect of ankle taping and bracing on vertical ground reaction forces during drop landings before and after treadmill jogging

STUDY DESIGN

Single-group repeated-measures experimental design.

OBJECTIVES

The purpose of this study was to evaluate the effects of prophylactic ankle stabilization on vertical ground reaction forces before and after treadmill jogging.

BACKGROUND

Previous research has demonstrated acute effects of ankle taping and bracing on ankle joint kinematics and vertical ground reaction forces during drop landings. Based on the number of investigations demonstrating increased range of motion of the braced or taped ankle following exercise, it may be plausible that the aforementioned landing alterations may return to normal following an exercise bout.

METHODS AND MEASURES

Fourteen healthy recreational participants performed stiff and soft drop landings before and after a 20-minute treadmill exercise bout under 3 different ankle stabilizer conditions (no stabilizer, ankle brace, and ankle tape). A forceplate was used to collect ground reaction force data under the dominant foot. The first and second peak impact force, as well as the time to each of the 2 peak forces, were determined for each trial and used as dependent variables.

RESULTS

The time to reach peak forces were significantly less under the ankle brace and tape conditions in comparison to the control (no-stabilizer) condition.

CONCLUSIONS

It appears that ankle taping and bracing decrease the time to reach peak impact forces. These alterations indicate that during dynamic activity the musculoskeletal structures of the body may be subjected to loads within shorter time periods. Whether these effects are detrimental over time remains speculative at this point and requires further research.

Does taping influence electromyographic muscle activity in the scapular rotators in healthy shoulders?

Although taping techniques are commonly used in addition to exercise programmes in the rehabilitation of shoulder instability and secondary subacromial or internal impingement, few studies exist on the effect of taping on the muscle activity of the scapular rotators. The purpose of our study was to examine the influence of one particular tape on muscular activity in scapular muscles. Twenty healthy shoulders were examined with surface EMG recordings on the three parts of trapezius and serratus anterior muscle during dynamic full range of motion abduction and forward flexion. The movement direction, and tape and no-tape conditions were randomized. The statistical analyses with ANOVA repeated Measures (GLM model) showed significant differences among the means between the four muscles (P<0.05), two movement directions (P<0.05), applied resistance (P<0.01), and movement period (P<0.01). However, no significant difference was observed based on the application of tape. The results of our investigation revealed no significant influence of tape application on EMG activity in the scapular muscles in healthy subjects. Future research will be necessary to examine other parameters of neuromuscular control in order to determine possible proprioceptive changes in muscle recruitment with tape application.

Is it possible to prevent sports injuries? Review of controlled clinical trials and recommendations for future work

Sports injuries are one of the most common injuries in modern western societies. Treating sports injuries is often difficult, expensive and time consuming, and thus, preventive strategies and activities are justified on medical as well as economic grounds. A successful injury surveillance and prevention requires valid pre- and post-intervention data on the extent of the problem. The aetiology, risk factors and exact mechanisms of injuries need to be identified before initiating a measure or programme for preventing sports injuries, and measurement of the outcome (injury) must include a standardised definition of the injury and its severity, as well as a systematic method of collecting the information. Valid and reliable measurement of the exposure includes exact information about the population at risk and exposure time. The true efficacy of a preventive measure or programme can be best evaluated through a well-planned randomised trial. Until now, 16 randomised, controlled trials (RCT) have been published on prevention of sports injuries. According to these RCT, the general injury rate can be reduced by a multifactorial injury prevention programme in soccer (relative risk 0.25, p < 0.001, in the intervention group), or by ankle disk training, combined with a thorough warm-up, in European team handball [odds ratio 0.17; 95% confidence interval (CI) 0.09 to 0.32, p < 0.01]. Ankle sprains can be prevented by ankle supports (i.e. semirigid orthoses or air-cast braces) in high-risk sporting activities, such as soccer and basketball (Peto odds ratio 0.49; 95% CI 0.37 to 0.66), and stress fractures of the lower limb by the use of shock-absorbing insoles in footwear (Peto odds ratio 0.47; 95% CI 0.30 to 0.76). In future studies, it is extremely important for researches to seek consultation with epidemiologists and statisticians to be certain that the study hypothesis is appropriate and that the methodology can lead to reliable and valid information. Further well-designed randomised studies are needed on preventive actions and devices that are in common use, such as preseason medical screenings, warming up, proprioceptive training, stretching, muscle strengthening, taping, protective equipment, rehabilitation programmes and education interventions (such as increasing general injury awareness among a team). The effect of a planned rule change on the injury risk in a particular sport could be tested via a RCT before execution of the change. The most urgent needs are in commonly practised or high-risk sports, such as soccer, American football, rugby, ice hockey, European team handball, karate, floorball, basketball, downhill skiing and motor sports.

The influence of rigid taping on peroneal latency in normal ankles

Traumatic ankle injury is a frequent clinical presentation. Ankle taping is commonly used in the prophylaxis of sprains and as an adjunct during rehabilitation of ankle injury. The mechanisms behind taping remain unclear however, one possible mechanism is improved proprioception and peroneal reflex responses. This study investigated the peroneal reflex response to rapid inversion (using a trapdoor) with different taping protocols. The dominant leg of 31 healthy subjects was tested in three conditions: no taping; simple prophylactic taping;and circumferential leg taping. A repeated measures ANOVA revealed no statistically significant effect across conditions or trials. The results suggest that neurophysiological responses to sudden inversion are not altered by mechanical or sensory input from taping in normal subjects.

Effect of ankle disk training combined with tactile stimulation to the leg and foot on functional instability of the ankle

Twenty-two university students with unilateral functional instability of the ankle participated in this study. They were randomly assigned to one of two experimental groups. Subjects in both groups were trained to stand on the affected limb on an ankle disk. In group 1, two pieces of 1-cm wide nonelastic adhesive tape were applied to the skin around the lateral malleolus from the distal third of the lower leg to the sole of the foot before the training sessions. Subjects in group 2 participated in the training sessions without the application of the adhesive tape. Training was performed for 10 minutes a day, five times per week, for a period of 10 weeks. Subjects were tested for postural sway while standing on the affected limb before, during, and after the training period. In group 1, postural sway values decreased significantly after 4 weeks compared with the pretraining performance, and they were within the normal range after not more than 6 weeks of training. In group 2, the values did not improve significantly compared with the pretraining performance until after 6 weeks of training, and they were not within the normal range until after 8 weeks of training. The findings suggest that the 2-week earlier correction of postural sway in group 1 was due to an increased afferent input from skin receptors that were stimulated by the traction of the adhesive tape.